C172 PLT ENTERED NKX CLASS D WITHOUT CLRNC.

Narrative

ABOUT 1/2 HR BEFORE MY FLT FROM HEMET-RYAN TO ENSENADA; MEXICO; I OBTAINED A TELEPHONE BRIEFING. WHEN DISCUSSING THE NOTAMS; THE BRIEFER MENTIONED THE AIR SHOW AT MIRAMAR WITH A FLT RESTR BELOW 16000 FT AND WITHIN A 5 NM RADIUS OF THE ARPT FROM 1500-2130 FT. HE THEN SAID SOMETHING TO THE EFFECT OF: 'DISREGARD; IT'S ALREADY OVER.' THIS MADE SENSE TO ME SINCE XA30Z IS EQUIVALENT TO XB30 LCL TIME (PDT); AND BRIEFING TIME WAS AROUND XB50. BEING A FRIDAY; IT SOUNDED LIKE THIS WAS A MORNING PRACTICE SESSION FOR THE AIR SHOW PLTS FOR THE AIR SHOW ON SATURDAY AND SUNDAY. MY PLAN HAD BEEN TO TAKE A DIRECT RTE FROM HEMET TO POGGI (VOR) AND GET A CLASS B CLRNC. SINCE I WAS UNABLE TO GET THE CLRNC WHEN IN THE ESCONDIDO AREA (I ASSUMED THAT FRIDAY AFTERNOON TFC WAS HVY; THE FREQ CONGESTION BORE THIS OUT). I DIVERTED TOWARDS THE COAST TO USE THE VFR CORRIDOR OVER LINDBERGH FIELD. ALTHOUGH THIS WAS MY FIRST TIME FLYING IN THE AREA; I HAD STUDIED THE SAN DIEGO TAC THE PREVIOUS EVENING AND FELT COMFORTABLE WITH TRANSITIONING THIS AIRSPACE. I THOUGHT NOTHING MORE OF THIS UNTIL I WAS ASKED BY SAN DIEGO BROWN FIELD TWR (WHO I HAD CONTACTED PRIOR TO XING THE BORDER); TO CALL A CERTAIN PHONE NUMBER; 'ASK FOR MR X OR MR Y BECAUSE OF A POSSIBLE 'SCRAPING' OF THE TEMPORARY RESTR AIRSPACE AT MIRAMAR.' ALTHOUGH I MADE SEVERAL ATTEMPTS TO CONTACT MR X OR MR Y AT THIS NUMBER AND OTHERS; I HAVE BEEN UNSUCCESSFUL SO FAR. TODAY; I GOT THE IDEA THAT I WAS SUPPOSED TO CONTACT A MR XY SO I WILL MAKE ANOTHER ATTEMPT ON MONDAY. MY ASSUMPTION IS THAT THE NOTAM TIME WAS GIVEN IN LCL TIME; BUT WITHOUT THE 'LT' FOLLOWING THE TIME INDICATION AND THAT THE BRIEFER ASSUMED THAT THIS WAS A UTC TIME. I AM VERY CONCERNED ABOUT THE SAFETY ISSUES ASSOCIATED WITH THE USE OF BOTH UTC AND LCL TIME ON NOTAMS WITHOUT CLR IDENT OF WHICH TIME IS IN USE. I BELIEVE THAT THE INDICATOR 'Z' OR 'LT' SHOULD BE USED FOR EVERY TIME INDICATION IN A NOTAM. FORTUNATELY; IT DOES NOT APPEAR THAT THERE WAS ANY KIND OF TFC CONFLICT.